Fisheries Economics and 20 Years with Marine Resource Economics: A Citation Analysis

Abstract This paper reviews the impact of articles published in the Marine Resource Economics (MRE) and within the field of fisheries economics in general over the period 1954–2004. Specific attention is given to the years 1984–2004, which is the period that MRE has been published. The degree of influence is assessed using citation analysis. I present the most cited papers in MRE, the top ten all time cited fisheries economics papers, and the most cited papers during each decade over the last 30 years. By analysing the trend of recently published papers, I can assess which ones are projected to be most influential. Keywords: Fisheries economics, Marine Resource Economics, ISI. JEL Classification Code: Q22.Fisheries economics, Marine Resource Economics, ISI, Resource /Energy Economics and Policy, Q22,

STOCHASTIC PRODUCTION AND HETEROGENEOUS RISK PREFERENCES: COMMERCIAL FISHERS' GEAR CHOICE

As long as total effort cannot be completely controlled, a more thorough understanding of fishers' supply response decisions will be beneficial for fisheries managers. In this paper, we present a model of fishers' gear choice, which is empirically estimated on a panel of Swedish demersal trawlers. The approach allows for heterogeneity both in production technology and in risk preferences. Stochastic revenue functions with fixed effects are estimated and used to predict expected revenue and standard deviation for each trip. We employ a linear utility function in the mean-standard deviation framework and then analyze the gear choices, using the predicted values together with vessel capacity and lagged variables for the previous trip in a random parameters- logit model, which allow for heterogeneous preferences. The results indicate that fishers have a strong tendency to choose the same gear used on the previous trip, while in general they react to changes in economic and biological conditions by responding positively to increases in expected landing and negatively to increases in the variability of the expected landing values, indicating risk aversion.Risk and Uncertainty,

A BIOECONOMIC ANALYSIS OF THE SWEDISH FISHERY FOR NORWAY LOBSTER (NEPHROPS NORVEGICUS)

A modified version of Jones' length-based cohort analysis is linked to economic data from the Swedish trawl fishery for Norway lobster (Nephrops norvegicus). The current regulation implies a fishing practice where each landed lobster entails three killed due to discard mortality, and different cases of trawl selectivity are compared together with varying natural mortality. The bioeconomic analysis shows that a maximum economic yield equilibrium requires effort reductions of more than 50%, leading to a potential resource rent of almost US $3 million, compared to the open-access situation in 1995. Further increase of the resource rent is possible if a more selective trawl is introduced and enforced. The trawl fishery is compared with a minor in-shore creel fishery, which differs in exploitation pattern, fuel consumption, and impact on the benthic flora and fauna. A qualitative discussion on the two fisheries is carried out and a comparison of the economic performance is presented.Resource /Energy Economics and Policy,

Small-scale Fishermen and Risk Preferences

Using an experimental approach, we investigate the risk preferences of artisanal fishermen in Tanzania waters of Lake Victoria. The experiment concerns pairwise comparisons of hypothetical fishing trips that vary in expected mean and spread of the net revenue. The results show that about 34% of the fishermen can be considered as risk neutral, 32% as risk averse, and 34% as risk seekers. Econometric analysis indicates that the likelihood of belonging to the risk-seeking group increases if motorboats are used, if fishing is the main source of household income, and if the fisherman is targeting Nile perch. Asset ownership and perhaps socioeconomic variables influence risk preferences.Risk aversion, artisanal fishermen, Tanzania, Lake Victoria, Nile perch, dagaa, Institutional and Behavioral Economics, Resource /Energy Economics and Policy, Q22,

What Do Respondents Bring to Contingent Valuation? A Comparison of Monetary and Labor Payment Vehicles

With contingent valuation, both the goods being valued and the payment vehicles used to value them are mostly hypothetical. However, although numerous studies have examined the impact of experience with the good on willingness to pay, less attention has been given to experience with payment vehicles. This paper examines how this influences responses to a contingent valuation scenario of maintenance for irrigation canals. Specifically, the paper uses a split-sample survey to investigate the effects of experience with monetary and labor payment vehicles on the acceptance of a contingent valuation scenario and protest bids. Using convergent validity tests, we found that experience acquired from using both monetary and labor payment vehicles reduces the asymmetries in acceptance rates. These findings suggest that experience with payment vehicles reduces time/money response asymmetries in the contingent valuation method.contingent valuation, payment vehicles, numéraires, experience

Technical Efficiency in the Swedish Trawl Fishery for Norway Lobster

To reduce fleet capacity in European fisheries is an important objective of the European Union’s Common Fisheries Policy. The success of such programmes depends both on the variation and the level of efficiency within the fishing fleets. If vessels with significantly lower efficiency level than average are decommissioned, the actual reduction in fishing capacity will be less than expected. Further, if the remaining vessels after a decommissioning program are not operating at an efficient level, future improvement in efficiency may even further offset the effects of the decommissioning program. This paper examines the level and determinants of technical efficiency for a sample of Swedish demersal trawlers, which mainly target Norway lobster but also shrimps and demersal fish in 1995. The data on per-trip gross revenues, fishing effort, gear choice, month of fishing and vessel attributes are analyzed using a translog stochastic production frontier, including a model for vessel-specific technical inefficiencies. Output elasticities and returns to scale are also examined. The technical inefficiency effects are found to be highly significant in explaining the levels and variation in vessel revenues. The mean efficiency for the sample vessels is estimated to be 66%. The inefficiency model indicates that efficiency decrease with total annual effort, and the same applies with vessel size in Gross Registered Tonnage. Further, it is found that older vessels are less efficient

Regulatory Compliance in Lake Victoria Fisheries

Lake Victoria is the worlds' second largest and Africa's largest fresh water body and shared by Kenya, Uganda and Tanzania. The Nile perch was introduced to Lake Victoria in the 1950s and experienced explosive population growth in the 1970s. Since the 1990s landings have been above or about 500 000 tons mainly consisting of three species, the Nile perch, tilapia and dagaa. The open access fishery has experienced a dramatic decline in catch per vessel and to compensate many fishers violate the regulation by using smaller mesh size than legal minimum size. This paper analyzes the causes of regulatory compliance in a developing country context. In addition to traditional deterrence variables such as risk of detection and expected gains from violation, we explore potential reasons for following the rules such as being moral and doing the right thing, obeying the rules due to peer pressure from other fishers, perceiving the regulation as legitimate, and perceiving that they (the fishers) have been involved in the regulation process. We use self-reported data from Tanzanian artisanal fishers in Lake Victoria and focus our analysis on the minimum mesh-size regulation. The results indicate that fishers adjust their violation rate with respect to changes in deterrence variables such as probability of detection and punishment. Fishers also react to legitimacy and social variables, which inter alia means complying more when they perceive the regulation to be legitimate as well as when they are influenced by peer groups. We also find a small group of persistent violators who appear to react neither to normative aspects nor to traditional deterrence variables. These fishers systematically violate the mesh-size regulation and when arrested, bribe their way out of punishment

The Regulatory Effect on Productivity Development: Comparison of Icelandic, Norwegian and Swedish Fisheries

Several factors contribute to the productivity of nations' fisheries: (1) The biophysical conditions that determine the abundance of fish stocks, (2) government regulation of fisheries, and (3) innovation and adoption of (i.e. investments in) new fishing technologies. This paper analyzes the long-run productivity performance of three Nordic countries Iceland, Norway and Sweden. These countries offer a rich variety in fisheries management strategies. Iceland has a fully developed individual transferable catch quota (ITQ) system, Norway has since quite some time individual catch quotas (IQ) with limited transferability, while Sweden also uses TACs (Total Allowable Catch) but within a regulated open-access framework, i.e., individual fishers still race for the catch. Our paper analyzes the evolution of the industry's productive performance in light of industry structure and government policies towards the fisheries sector in these two countries. The analysis is supported by econometric productivity estimates of these countries performance using annual data from 1960 to 2003 for several competing production model specifications. Our econometric production models provide estimates of such measures as technical progress, labor productivity growth and total factor productivity growth. This analysis allows us to draw conclusions on the long-run evolution of economic performance without undue influence of shorter biological cycles in important fish stocks and other type of shocks. We find productivity gaps between the countries according to several productivity measures we employ, and discuss the evolution and sources of these differences

Aggregation Level and Prediction of Fishing Vessel Behavior and Productivity

Fishing overcapacity has lead to unsustainable harvesting and rent dissipation in global fisheries. Only government intervention of some kind can lead to a reduction in capacity. If efficiency is the primary objective for the regulator, then the least efficient vessels should be decommissioned. Here we analyze the Swedish fishery using a panel of individual fishing trip observations. Trip data provide some additional information compared to annual vessel data that could be exploited at both aggregation levels. The effect of data aggregation choice on estimated vessel behavior and productivity is examined. Productivity estimates are utilized in a Probit model of exit from the fishery. We also estimate returns to diversification and obtain some interesting results on the tradeoff between trip length and number of trips.Keywords: Theoretical and Empirical Bio-Economic Modelling, productivity, fishing vessels, exit, Fisheries Economics, AggregationKeywords: Theoretical and Empirical Bio-Economic Modelling, productivity, fishing vessels, exit, Fisheries Economics, Aggregatio

Effectiveness and safety of opicapone in Parkinson’s disease patients with motor fluctuations: the OPTIPARK open-label study

Background The efficacy and safety of opicapone, a once-daily catechol-O-methyltransferase inhibitor, have been established in two large randomized, placebo-controlled, multinational pivotal trials. Still, clinical evidence from routine practice is needed to complement the data from the pivotal trials. Methods OPTIPARK (NCT02847442) was a prospective, open-label, single-arm trial conducted in Germany and the UK under clinical practice conditions. Patients with Parkinson’s disease and motor fluctuations were treated with opicapone 50 mg for 3 (Germany) or 6 (UK) months in addition to their current levodopa and other antiparkinsonian treatments. The primary endpoint was the Clinician’s Global Impression of Change (CGI-C) after 3 months. Secondary assessments included Patient Global Impressions of Change (PGI-C), the Unified Parkinson’s Disease Rating Scale (UPDRS), Parkinson’s Disease Questionnaire (PDQ-8), and the Non-Motor Symptoms Scale (NMSS). Safety assessments included evaluation of treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs). Results Of the 506 patients enrolled, 495 (97.8%) took at least one dose of opicapone. Of these, 393 (79.4%) patients completed 3 months of treatment. Overall, 71.3 and 76.9% of patients experienced any improvement on CGI-C and PGI-C after 3 months, respectively (full analysis set). At 6 months, for UK subgroup only (n = 95), 85.3% of patients were judged by investigators as improved since commencing treatment. UPDRS scores at 3 months showed statistically significant improvements in activities of daily living during OFF (mean ± SD change from baseline: − 3.0 ± 4.6, p < 0.0001) and motor scores during ON (− 4.6 ± 8.1, p < 0.0001). The mean ± SD improvements of − 3.4 ± 12.8 points for PDQ-8 and -6.8 ± 19.7 points for NMSS were statistically significant versus baseline (both p < 0.0001). Most of TEAEs (94.8% of events) were of mild or moderate intensity. TEAEs considered to be at least possibly related to opicapone were reported for 45.1% of patients, with dyskinesia (11.5%) and dry mouth (6.5%) being the most frequently reported. Serious TEAEs considered at least possibly related to opicapone were reported for 1.4% of patients. Conclusions Opicapone 50 mg was effective and generally well-tolerated in PD patients with motor fluctuations treated in clinical practice. Trial registration Registered in July 2016 at clinicaltrials.gov (NCT02847442)